Superconductivity and antiferromagnetism in boron-rich lattices

Ferromagnetism, antiferromagnetism, or superconductivity has been discovered in most hexa- and dodecaborides.     

Potato germplasm collecting expedition to the Guaitecas and chonos Archipelagos,Chile, 1990

Summary A joint Chilean, Italian, and United States potato (Solanum tuberosum) germplasm collecting expedition was conducted in the Guaitecas and Chonos Archipelagos, south of Chiloé Island, between March 4 – March 21, 1990. The expedition resulted in 30 collections ofSolanum tuberosum and 1 collection ofFragaria chiloensis L. Twenty-three of the potato collections were along the salt-water-swept shores of the islands. These beach populations, unlike the indigenous landraces in southern Chile, are self-perpetuating populations and provide useful new germplasm for researchers interested in the origin of cultivated potatoes and in the origin ofSolanum tuberosum in Chile.     

The effects of human trampling on the microbiological properties of soil and vegetation in mediterranean mountain areas

Increased tourist activity and recreational use of wilderness and other protected areas has endangered zones of high environmental value. The aim of this work was to evaluate the effects of trampling intensity (low, high use trails and untrampled trails) and distance from the trails (on the trails, at 10 and 20 m from the trails) on the vegetation, chemical, physical and microbiological properties of a soil in Mediterranean mountain areas. Trail type and distance from the trail significantly influenced several parameters. High use trails showed lower values of plant cover and diversity of vegetation species, as well as soil respiration and some enzyme activities (phosphatase, β‐glucosidase and dehydrogenase) than low use trails. In addition, the effects of trampling spatially extended further from these high use trails than from low use trails. Statistical analysis showed that some microbiological (basal respiration, dehydrogenase activity and β‐glucosidase activity) and vegetal parameters (plant cover and diversity) may be established as a set of indicators for the evaluation of soil quality on these areas subjected to human trampling. We concluded that trampling significantly impacts on soil microbial processes and vegetal communities, and visitor should be restricted from entering ecologically sensitive areas due to the effects of trampling. Copyright © 2010 John Wiley & Sons, Ltd.     

Pharmacokinetics and bioequivalence of two suxibuzone oral dosage forms in horses

A disposition and bioequivalence study with a suxibuzone granulated and a suxibuzone paste oral formulation was performed in horses. Suxibuzone (SBZ) is a nonsteroidal anti-inflammatory drug, which was administered to horses (n = 6) at a dosage of 19 mg/kg bwt by the oral route (p.o.) in a two period cross-over design. Suxibuzone is very rapidly transformed into its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ). Therefore plasma and synovial fluid concentrations of SBZ, PBZ and OPBZ were simultaneously measured by a sensitive and specific high-performance liquid chromatographic method. The pharmacokinetic parameters were determined by noncompartmental analysis. Suxibuzone could not be detected in any plasma and synovial fluid samples (< 0.04 microgram/mL). Plasma PBZ and OPBZ concentrations were detected between 30 min and 72 h after granulate and paste administration. Mean plasma concentration of PBZ peaked at 5 h (34.5 +/- 6.7 micrograms/mL) and at 7 h (38.8 +/- 8.4 micrograms/mL), and mean area under the concentration-time curve (AUC0-->LOQ) was 608.0 +/- 162.2 micrograms.h/mL and 656.6 +/- 149.7 micrograms.h/mL after granulate and paste administration, respectively. Mean plasma concentration of OPBZ increased to 5-6.7 micrograms/mL, with the maximum concentration (Cmax) appearing between 9 and 12 h after administration of both formulations. The AUCs0-->LOQ for OPBZ were also similar (141.8 +/- 48.3 micrograms.h/mL granulate vs. 171.4 +/- 45.0 micrograms.h/mL paste). It was concluded that the suxibuzone products were bioequivalent with respect to PBZ. For OPBZ, the 95% confidence intervals of the pharmacokinetic parameters were within the acceptable range of 80-125%. The paste formulation provided greater bioavailability of PBZ and OPBZ.     

Are species genetically more sensitive to habitat fragmentation on the periphery of their range compared to the core? A case study on the sand lizard (<Emphasis Type="Italic">Lacerta agilis</Emphasis>)

Context

Species show different sensitivity to habitat loss and fragmentation depending on their specialization. Populations of a species at the range margin are generally assumed to be more stenoecious than populations at the core of the distribution and should therefore be more sensitive to habitat fragmentation.

Objectives

We evaluated the hypothesis that fragmentation effects species more strongly at the range periphery of their range compared to the core, resulting in lower genetic variability in comparable patch sizes and lower gene flow among populations.

Methods

We compared the genetic diversity and structure of five sand lizard (Lacerta agilis) populations at the margin of its range in Bulgaria and of 11 populations at the core of its distribution in Germany. We based the analysis on microsatellites, comprising 15 loci in Bulgaria and 12 in Germany.

Results

All diversity indices declined with patch size. For medium-sized patches all diversity indices were lower at the range periphery compared to the core, with two of them being significant. AIC_c based model selection showed strong support for core/periphery and patch size effects for observed and expected heterozygosity but only a patch size effect for allelic richness. There was no isolation-by-distance and each sampled population was allocated to a separate cluster with high probability for both countries, indicating that all populations are (almost) completely isolated.

Conclusion

Our study indicates an increased sensitivity of a species to fragmentation at the periphery compared to the core of its distribution. This differential sensitivity should be accounted for when prioritizing species based on their fragmentation sensitivity in landscape management.